Solar Thermal Systems
Solar hot water systems, also called solar thermal systems, utilize the sun’s energy by generating heat. This heat is stored in water. (By contrast solar PV systems generate electricity which is fed to the national grid or stored in batteries).
The sun is the source of all our energy. This energy travels through the vacuum of space and is received on earth as radiation. When radiation (light) strikes matter the molecules of that matter vibrate causing friction and therefore heat. This happens even on a cold or cloudy day albeit to a lesser extent.
Solar collectors are selectively coated to absorb this light as completely as possible and minimize thermal radiation losses. Solar radiation is even present on cloudy and cold days and useful at all latitudes in all climates. By using vacuums and insulation it is possible to prevent much heat loss.
Solar ST Case Studies
Solar and air source heat pump
These Velux flat plates (lower centre) are integrated into the zinc roof of this eco-build property. The solar heat is delivered to a 185 litre pressurised hot water cylinder which is also connected to a Genvex air source heat pump.
Flat roof
This Thermomax DF100 collector was installed on a flat garage roof. The tubes are rotated to better intercept incoming solar radiation.
Thermomax evacuated tube collector
This Thermomax evacuated tube collector is mounted in 'landscape' format. The solar fluid is pumped around each tube so giving a high heat exchange surface area. The versatility of such a system enables installation on flat roofs, pitched roofs and vertical walls as well as on ground-mounted frames.
Indoor Pool
180 evacuated tubes supply heat to this indoor pool. A stainless steel heat exchanger is placed in the pool pipework upstream of the pool boiler. In this way the solar system pre-heats the pool water. Since pools use a lot of energy to come up to temperature the solar system can take a significant load off the pool boiler early in the season. In many cases the boiler can be switched off for much of the swimming season since the solar system can provide sufficient heat on its own. These customers report a marked reduction in their oil bills.
East-west system
These Thermomax collectors were installed on east and west-facing roofs. Each collector has its own pump to deliver heat to the solar cylinder.
Combi boiler + solar
Solar energy heats this pressurised cylinder in the loft. If the water is hot enough it is directed to the hot taps. If it is not hot enough it is directed to the combi boiler for further heating.
Velux-style collectors
These 6 x Velux flat plate collectors blend in well to the roof and sit alongside the Velux windows for an integrated look.
Solar and ground source heat pump
Renewable Heat Incentive
The details of the Renewable Heat Incentive (RHI) are still being finalized. We recommend you to look at the OFGEM link below for further details:
BENEFITS OF SOLAR THERMAL IN THE UK
Save money
Insolation in the UK is sufficient to provide an average of 60% of a household’s annual hot water requirements. In the southeast it is not uncommon to get well over 90% of your hot water requirements between the months of April to September. During the other 6 months the solar system can pre-heat the incoming cold mains water to between 20-40°C. This means that your boiler has considerably less work to do.
Minimize your environmental impact
Burning fossil fuels produces vast amounts of carbon dioxide, a major contributor to global warming. The average household with a 3m² solar system installed can expect to generate approximately 2,256 kWh/year with zero emissions.